الفهرس 
Homogenous nucleationOnly 14 pages are availabe for public view
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Abstract
One of the most important factors in the casting properties are controlling in solidification process. Since the solidification begins with nucleation, therefore controlling in nucleation provides controlling in casting mechanical properties. There are many authors proposed a lot of mathematical nucleation models. It was concerned in this work on experimental and numerical treatment of the heterogeneous grain nucleation happening during solidification of the Al-4%Cu alloy as an example on aluminum alloys The free growth model is adopted within a multi-phase flow and solidification simulation model coupled to a FLUENTTM software to model grain nucleation. The grain density and the undercooling were correlated via lognormal distribution function and three alloy-characteristic fitting parameters that the total grain density, the mean undercooling and the standard deviation of the undercooling. Numerical case study using different mesh size was proposed to represent the results which can be obtained. . Nucleation parameters of the used model was determined. An experimental benchmark used in the verification of the mathematical model was constructed and equipped with a cooling system and one thermocouples to capture cooling rates at a check point. The resulting cooling curve, undercooling and the corresponding grain densities for grain refined Al-4%Cu alloy were measured. All of the measured results were used to validate the used model. The resulting grain density and size, macrostructure, cooling curve and undercooling exhibited good agreement.